title: Variable optical attenuator based on photonic crystal waveguide with low-group-index tapers.
abstract: We demonstrate a compact thermo-optic variable optical attenuator (VOA) based on the cutoff effect of W1 photonic crystal waveguide (PCW). In experiment, a variable attenuation range of 29 dB is achieved with a device length of only 16.8 μm. The coupling loss is also reduced by 7.5±2.5 dB through introducing low-group-index tapers between the W1 PCW and strip waveguide. This VOA provides the largest variable attenuation range in the reported tunable PCW device to our knowledge.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhao
authors.forename: Kaiyu
authors.initials: K
authors.lastname: Cui
authors.forename: Xue
authors.initials: X
authors.lastname: Feng
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Yidong
authors.initials: Y
authors.lastname: Huang